Are you arguing that Uber’s business model isn’t sustainable or that it’s bad for both parties? Uber being in the red doesn’t mean it’s a net negative for everyone.
Operating at a loss drives out anyone who doesn't have the money to burn forever to compete with you, and when the market is yours you can re-align prices to allow profit. This seems clear to me and the 'net negative' is that you don't actually have a free market anymore. Inserting yourself between product and fulfillment and taking the surplus value that would have gone to either customer or producer is not a gain for anyone but the people who invested in the rent-seeker.